There are several resin- or membrane-based kits able to
separate DNA from RNA (moreorless). At least one rep told
me that the material is silica and the separation is based
binding and washing buffers. This kit works.
HOWEVER: Using their buffers with silicapowder or membrane
from other sourses - there's no separation.
This material is probably not diatomaceous earth since I'm
not talking about Bio-Rad who has the patent (US 5,075,430).
Several firms sell this kind of product, so it's not propable
that they all would have developed "a modified silica" able
to bind RNA but not DNA.
SO - ANYBODY HAVE AN IDEA WHAT THIS MATERIAL IS.